Synthesis of Functionalized Heterocycles by C-H Activation Hydrocarbons are the simplest and most abundant chemical feedstock available on the planet. Despite this, few efficient methods exist for their selective functionalization. Much attention is being focused on C-H activation problems in contexts ranging from methane to complex molecule total synthesis. Obvious problems include issues of reactivity, selectivity, and functional group compatibility. Recognizing the synthetic potential of the C-H activation process, this proposal seeks to elucidate mechanistic details relevant to its use. Particularly, the metal-catalyzed oxidative dimerization of heteroarenes and related substrates will be investigated. The specific aims are 1. Establish the factors governing the selectivity of dehydrogenative C-C coupling and elucidate additional details of its mechanism; 2. Determine practical and efficient conditions for the reoxidation of the catalytic species in this process described above; 3. Establish conditions for the oxidative heterodimerization of N-heterocycles with other arenes and related substrates.